The mobile phone industry is moving rapidly toward providing hardware upgradability for mobile device components. One likely upgrade may involve adding a second Wi-Fi® radio, or more, to improve wireless local area network (WLAN) connectivity and provide better performance. Adding a second, or even multiple, WLAN integrated circuits (ICs) to create parallel data paths for the mobile device creates challenges in that independent radios must contend for the same medium at the Media Access Control (MAC) Layer and at the physical (PHY) layer.
An example known multiple radio system 100 is shown in FIG. 1. The multiple radio system 100 includes a processor 101 with a first network interface 102 that uses a first MAC address and a second network interface 105 that uses a second MAC address. The network interfaces are software access points to the processor 101. A first radio system, WLAN subsystem 104, includes WLAN hardware, a WLAN subsystem 1 driver and interfaces with an antenna system. A second radio system, WLAN subsystem 107, also includes WLAN hardware, a WLAN subsystem 2 driver and may interface with the same antenna system as first radio system, or may have a separate antenna system. In either case, the first WLAN subsystem 104 MAC Layer sends data transmissions 103 and also receives data via the network interface 102. The second radio system, WLAN subsystem 107 MAC layer similarly sends data transmissions 106 and also receives data via the network interface 105. The data transmissions 103 and data transmissions 106 are in contention at the MAC Layer and at the PHY layer in the wireless medium access, based on the backoff algorithm. Furthermore, each radio system uses a separate Internet Protocol address to communicate with a WLAN.